This invention relates generally to an information processing system of a relatively small size such as a personal computer, and more particularly to an information processing system having compact high speed auxiliary storage for data and programs.
A conventional information processing system is generally configured as shown in FIG. 14. Such a system comprises a central processing unit (CPU) 1 which is the heart of the system. CPU 1 is connected through system bus 26 to main storage 2 where programs and data transferred from the auxiliary storage and intermediate results of program execution are stored, read-only memory (ROM) 3 which stores a basic input/output system (BIOS), keyboard 4 which functions as an input device to the system, display 5 which functions as an output device, a hard disk 6, and a floppy disk 7 which function as auxiliary storage for programs and data.
When power is applied to the system, the system is reset and initialized and CPU 1 executes an initial load program (ILP) stored in BIOS ROM 3 to transfer other programs from hard disk 6 or floppy disk 7 to main storage 2. Thereafter, CPU 1 executes programs transferred to main storage 2 to accomplish the objectives of the programs.
Magnetic storage such as hard disk 6 or floppy disk 7 which are employed as auxiliary storage has a limit in terms of its possible size, weight and power consumption reduction. As a result, the presence of magnetic storage imparts a large restriction on the realization of a compact information system featuring actual portability.
Since the prior art floppy disk or hard disk drives include a mechanical rotary portion and a mechanical operation for moving a read/write head relative to a magnetic medium, access time can be necessarily long and the operation of the drive slow. Further, the mechanical operation involved during the access operation is noisy.
Beside the forgoing disadvantages, it is known that magnetic storage is relatively weak with respect to strong magnetic fields and high temperature and humid environments.
In order to avoid the problems encountered with magnetic storage, attempts have been made to use semiconductor based storage by following two different approaches. In the first approach, an application program, i.e., a data processing program which allows a user to visually interact with the program and confirm results, switches banks of the semiconductor auxiliary storage and access to the semiconductor auxiliary storage is accomplished deemed as a part of the main system storage. In the second approach, the access is made through a device drive program, i.e., a device driver, as a specific auxiliary storage and functions as a part of the operating system (OS).
However, in the first approach, the application program is designed to have a high dependency on a particular type and kind of memory. An existing application program is usually created and prepared on the assumption that a hard or floppy disk is employed as the auxiliary storage. Thus, it is necessary to modify the application program so that it may be employed with semiconductor type auxiliary storage.
In the second approach, after the device driver is activated, the semiconductor storage device is set in its activated condition. A BOOT program is stored in the semiconductor device and the main body of software cannot be set up as part of establishing an active condition. Therefore, it is not possible to store the OS itself in semiconductor auxiliary storage, nor to incorporate a medium copy program, i.e., copied into such storage, or from a floppy disk to floppy disk and, further, is dependent on a BIOS which is highly dependent on the OS.
It is an object of the present invention to solve the above mentioned problems.
It is another object of this invention to provide a compact, light weight, highly reliable, and high speed information processing system while permitting the utilization of existing software applications and programs created and written for use with particular conventional memory devices, such as floppy disk or hard disk magnetic memories.